The expression of ER stress markers in Raw264.7 cells infected with live or heat-killed Mtb H37Rv.

<p>Raw264.7 cells were infected with live or heat killed Mtb H37Rv (MOI = 1 to 10) for 3 h, and then incubated for 48 h in the presence or absence of L-NAME or NAC. (A, D, E) Immunoblot analysis was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0028531#s4" target="_blank">Materials and Methods</a>. Representative data from three independent experiments are shown. (B) Effect of Mtb H37Rv infection on nitric oxide (NO) production was assessed indirectly by Griess reaction. (C) Representative flow cytometry histograms of superoxide at 48 h after Mtb H37Rv infection. Superoxide detection was evaluated by dihydroethidium (DHE) staining using flow cytometry. Data are means ± SEM of two independent experiments performed in triplicate. CHOP expression analysis after treatment with N-nitro-L-arginine methyl ester (L-NAME), a nitric oxide inhibitor (D) and N-acetyl-L-cysteine (NAC), a superoxide inhibitor (E). The statistical significance (*<i>P</i><0.05, **<i>P</i><0.01 and ***<i>P</i><0.001) of observed differences between inhibitor treated and untreated groups following infection with Mtb H37Rv were verified by two-tailed t-test.